1. Field of the Invention
This invention relates to tools for installing clamps to repair a bone fracture and methods therefore and, more particularly, to a tool for installing a clamp of the type that is threaded through a hole drilled through a fractured bone, and method therefore.
2. Description of the Prior Art
One treatment procedure for a fractured bone is to drill a hole therethrough that intersects the fracture. The hole is used for installation of a type of clamp which applies a force that holds the fractured bone together. A clamp of this type is disclosed in U.S. Pat. No. 4,796,612 of Hewitt W. Reese (referred to hereinafter as a Reese clamp) which is hereby incorporated herein and made a part hereof.
The Reese clamp is made of an elastically deformable material molded to form a hook and a shank, at respective ends thereof. The central portion of the Reese clamp is comprised of a plurality of similar right truncated cones that are coaxially disposed, with the base of one cone connected to the top of an adjacent cone. The cones are oriented with their bases towards the hook end.
The Reese clamp additionally includes a button having a central hole therethrough. The diameter of the hole through the button is intermediate to the diameters of the base and the top of the cones. The button is disposed upon the central portion, a portion of a cone thereof being within the central hole.
Because of the diameter of the button, the orientation of the cones and the elastic deformability of the material, the button and the central portion form a pawl and ratchet, respectively, where the button may be advanced towards the hook end, but not towards the shank end.
The hook may be elastically deformed from its original shape and threaded through the drilled hole. When threaded through, the hook to resumes its original shape.
The threaded through hook bears against a distal cortex of the bone in much the same way a toggle bolt bears against an interior surface of a wall. The button is thereafter advanced to bear against a proximal cortex of the bone, thereby holding the fractured bone together.
Although the Reese clamp has proven utility, there is a need for a simple, reliable, economic tool for installing the Reese clamp.